| 摘要 |
A body is provided with a SiO2 coating by (a) locating the body in a gaseous atmosphere, which may or may not have an element in common with the body (e.g. oxygen and a metal or Si compound), (b) igniting the atmosphere to precipitate e.g. the metal or Si oxide in particles which cover part of the surface only, and (c) completing formation of the coating by reaction of a gas, e.g. O2, with the surfaces of the body not already covered (when the body is Si), or by deposition of SiO2 from the gas phase. In Examples (a) a mixture of an organic Si compound and O2 is ignited to precipitate SiO2 on a Si body, which is then treated with O2 and/or H2O vapour, to give a continuous SiO2 layer, and (b) a mixture of an organic Al compound and O2 is ignited to precipitate Al2O3 on a Ge body, which is then treated with SiO2 containing gases to form a further layer containing SiO2 and some Al silicate (due to reaction with the Al2O3). |
